Barcelona , Spain -LRB- CNN -RRB- -- Microsoft unveiled Windows 8 for public testing on Wednesday in the hope that it will help the brand win back some of the ground it has been losing to Apple and Google .

The new operating system works on tablets as well as PCs and laptops , connecting them via the cloud to give users a more consistent experience as they switch between devices .

`` It 's beautiful , modern , fast and fluid -- it 's a generational change in the Windows operating system , '' Microsoft Windows President Steven Sinofsky said as he launched the consumer preview of the new operating system at Mobile World Congress , in Barcelona , Spain .

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Windows 8 scales across devices and screen sizes , Sinofsky said . `` There 's too many hard stops between phones and tablets and desktops . We want to make things more harmonious , '' he said .

The new operating system uses the `` Metro '' style of software currently being used on phones running the Windows 7 operating system , using tiles on the start-up screen .

A new Windows Store , which will be the marketplace for all apps for Windows 8 , also launched on Wednesday . Apps will be free to download for the duration of the consumer preview .

James Governor , a London-based tech-industry analyst , said Windows 8 was unlikely to galvanize Microsoft 's market profile but its entry into tablet technology laid crucial groundwork for sustained relevance .

He said the popularity of Windows 7 meant that , as was seen with Microsoft 's earlier XP operating system , there would n't be intense clamoring for an immediate update .

`` I do n't think it 's an explosive ` Christ , we 've got to have this new release , ' `` he said . `` There is n't necessarily a pent-up demand for what Windows 8 represents . ''

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Governor said the move into the tablet market represented by Windows 8 marked a key step for Microsoft as it repositioned itself against Apple and Android-powered machines .

`` Microsoft needs to be in the tablet game . It could n't sit out two or three rounds of tablets without trying to have a more effective play and clearly Windows 8 is a big part of that , '' he said .

In terms of functionality , Governor said Windows 8 suffered from a `` weird two-personality thing '' as it switched between its user-friendly new Metro interface into functional areas of computing .

`` A lot of people are n't going to be comfortable with that : here is this new Metro personality and then , oh by the way , now I really want some really hardcore web development . I found it OK , but I do n't know how it will work with others . ''

Barry Neild contributed to this story from London

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Microsoft has made available a preview version of its latest Windows software

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Windows 8 upgrade marks computing giant 's long-awaited move into tablets

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Analyst says success of Windows 7 means there wo n't be stampede to upgrade